Component carrier

ABSTRACT

The present invention is a surface mount component carrier comprised of a disk of insulating material having at least two apertures. The disk is substantially covered by a metalized ground surface and includes at least two conductive pads surrounding the apertures, and insulating bands which surround each conductive pad. The insulating bands separate and electrically isolates the conductive pads from the metalized ground surface. A surface mount component, such as a differential and common mode filter, is positioned lengthwise between the two conductive pads and operably coupled to the carrier. Once the surface mount component is coupled to the carrier, the combination can be manipulated, either manually or through various types of automated equipment, without subjecting the surface mount component to mechanical and physical stresses normally associated with the handling of miniature components. The carrier also provides the added benefit of improved shielding from electromagnetic interference and over voltage dissipation due to the surface area of the metalized ground surface. The same concept for the above described carrier is also incorporated into several alternate embodiments, either independently or embedded within electronic connectors.

TECHNICAL FIELD

[0001] This application is a continuation of copending application Ser.No. 09/945,329 filed Aug. 31, 2001, which is a continuation ofapplication Ser. No. 09/697,484 filed Oct. 26, 2000, which is acontinuation of both application Ser. No. 09/056,436 filed Apr. 7, 1998,now abandoned, and application Ser. No. 09/056,379 filed Apr. 7, 1998,now U.S. Pat. No. 6,018,448, which is a continuation-in-part ofapplication Ser. No. 09/008,769 filed Jan. 19, 1998, now U.S. Pat. No.6,097,581, which is a continuation-in-part of application Ser. No.08/841,940 filed Apr. 8, 1997, now U.S. Pat. No. 5,909,350. Thedisclosures of the foregoing applications are all incorporated herein byreference.

[0002] The present invention relates to a filter for protectingelectronic circuitry from electromagnetic field interference (EMI), overvoltages and preventing electromagnetic emissions. More specifically,this invention relates to a multi-functional electronic component whosephysical architecture suppresses unwanted electromagnetic emissions,both those received from other sources and those created internallywithin electronic circuitry by differential and common mode currents. Inaddition, due to the electronic component's physical architecture andmaterial composition, over voltage surge protection and magneticproperties can be integrally incorporated with the differential andcommon mode filtering and the invention relates to component carriersubstrates used to protect electronic components from mechanicalstresses associated with their handling and coupling within electronicequipment. The component carrier substrates also provide electricalinterference shielding and improved thermal characteristics.

BACKGROUND OF THE INVENTION

[0003] The majority of electronic equipment produced presently, and inparticular computers, communication systems, military surveillanceequipment, stereo and home entertainment equipment, televisions andother appliances include miniaturized components to perform new highspeed functions and electrical interconnections which according to thematerials from which they are made or their mere size are verysusceptible to stray electrical energy created by electromagneticinterference or voltage transients occurring on electrical lines.Voltage transients can severely damage or destroy such micro-electroniccomponents or contacts thereby rendering the electronic equipmentinoperative, and requiring extensive repair and/or replacement at greatcost.

[0004] Electrical interference in the form of EMI or RFI can be inducedinto electrical lines from such sources as radio broadcast antennas orother electromagnetic wave generators. EMI can also be generated fromthe electrical circuit which is desired to be shielded from EMI.Differential and common mode currents are typically generated in cablesand on circuit board tracks. In many cases fields radiate from theseconductors which act as antennas. Controlling these conducted/radiatedemissions is necessary to prevent interference with other circuitry orother parts of the circuit generating or sensitive to the unwantednoise. Other sources of interference are generated from equipmentcoupled to the electrical lines, such as computers, switching powersupplies and a variety of other systems, which may generate significantinterference which is desired to be eliminated to meet internationalemission and/or susceptibility requirements.

[0005] Transient voltages occurring on electrical lines can be inducedby lightning which produces extremely large potentials in a very shorttime. In a similar manner, nuclear electromagnetic pulses (EMP) generateeven larger voltage spikes with faster rise time pulses over a broadfrequency range which is detrimental to most electronic devices. Othersources of large voltage transients are found to be associated withvoltage surges occurring upon the switching off or on of some electronicpower equipment as well as ground loop interference caused by varyingground potentials. Existing protection devices, primarily due to theirarchitecture and basic materials, do not provide adequate protection ina single integrated package.

[0006] Based upon the known phenomenon of electromagnetic emissions andtransient voltage surges a variety of filter and surge suppressioncircuit configurations have been designed as is evident from the priorart. A detailed description of the various inventions in the prior artis disclosed in co-owned U.S. Pat. No. 5,142,430, herein incorporated byreference.

[0007] The '430 patent itself is directed to power line filter and surgeprotection circuit components and the circuits in which they are used toform a protective device for electrical equipment. The circuitcomponents comprise wafers or disks of material having desiredelectrical properties such as varistor or capacitor characteristics. Thedisks are provided with electrode patterns and insulating bands onsurfaces thereof which co-act with apertures formed therein so as toelectrically connect the components to electrical conductors of a systemeasily and effectively. These electrode patterns act in conjunction withone another to form common electrodes with the material interposed therebetween. The '430 patent was primarily directed toward filtering pairedlines. The present invention improves on the paired line concept byrefining and adapting the concept for use with low voltage low currentdata communication lines as well as arrangements directed towards highvoltage industrial and home applications such as three phase powerlines, electric motor noise filtering, LANs and other computer andelectronic devices.

[0008] Based upon the foregoing there was found a need to provide amulti-functioning electronic component architecture which attenuateselectromagnetic emissions resulting from differential and common modecurrents flowing within electronic circuits, single lines, pairs oflines and multiple twisted pairs. Such multi-functioning electroniccomponents are the subject of application Ser. No. 09/008,769, now U.S.Pat. No. 6,097,581, which is a continuation-in-part of application Ser.No. 08/841,940, now U.S. Pat. No. 5,909,350, both of which areincorporated herein by reference.

[0009] While the above referenced electronic components accomplish theirrespective tasks, usage of such components has been limited for a numberof reasons. First, the number of such components required continues toincrease as applications, such as data buses, continue to grow. Inaddition, as the number of required components grows, so does thephysical size of multi-component packages. Second, by their nature theelectronic components referred to are delicate structures which do nothandle physical stress well. During the manufacture of electronicproducts a number of mechanical stresses associated with handling andsoldering can damage the components.

[0010] Another drawback to using the referenced electronic components isthat it becomes very tedious to manually handle and mount the componentson electronic products being assembled. This often time translates intolower product yields and added expense due to broken or misconnectedcomponents.

[0011] A further disadvantage to some of the components is that theyinclude leads for thru-hole insertion. Physical stressing, bending orapplying torque to the leads can cause a failure in the final product,either immediately or later thereby affecting the products overallreliability.

[0012] Therefore, in light of the foregoing deficiencies in the priorart, the applicant's invention is herein presented.

SUMMARY OF THE INVENTION

[0013] Based upon the foregoing and because of the sensitive nature ofelectronic technology there is also a need for combining electromagneticfiltering with surge protection to eliminate the susceptibility to overvoltages and emissions from external sources. Due to the highlycompetitive nature of today's electronic industry such a differentialand common mode filter/surge protector must be inexpensive,miniaturized, low in cost and highly integrated to be incorporated intoa plurality of electronic products.

[0014] It is therefore a main object of the invention to provide aneasily manufactured and adaptable multi-functional electronic componentwhich filters electromagnetic emissions caused by differential andcommon mode currents.

[0015] It is another object of the invention to provide a protectivecircuit arrangement which may be mass produced and adaptable to includeone or more protective circuits in one component package to provideprotection against voltage transients, over voltages and electromagneticinterference.

[0016] Another object of the invention is to provide protective circuitshaving an inherent ground which provides a path for attenuating EMI andover voltages without having to couple the hybrid electronic componentto circuit or earth ground.

[0017] Another object of the invention is to provide a component carrierwhich is less susceptible to mechanical stresses and shock, more easilyassembled, surface mountable and capable of being used in automatedassembly.

[0018] These and other objects and advantages of the invention areaccomplished through the use of a plurality of common ground conductiveplates surrounding corresponding electrode plates separated by amaterial which exhibits any one or a combination of a number ofpredetermined electrical properties. By coupling pairs of conductors tothe plurality of common ground conductive plates and selectivelycoupling the conductors to electrode plates, line-to-line andline-to-ground component coupling is accomplished providing differentialand common mode electromagnetic interference filtering and/or surgeprotection. The circuit arrangement comprises at least one lineconditioning circuit component constructed as a plate. Electrodepatterns are provided on one surface of the plate and the electrodesurfaces are then electrically coupled to electrical conductors of thecircuit. The electrode patterns, dielectric material employed and commonground conductive plates produce commonality between electrodes for theelectrical conductors which produces a balanced (equal but opposite)circuit arrangement with an electrical component coupled line-to-linebetween the electrical conductors and line-to-ground from the individualelectrical conductors.

[0019] The particular electrical effects of the differential and commonmode filter are determined by the choice of material between theelectrode plates and the use of ground shields which effectively housethe electrode plates within one or more Faraday cages. If one specificdielectric material is chosen the resulting filter will be primarily acapacitive arrangement. The dielectric material in conjunction with theelectrode plates and common ground conductive plates will combine tocreate a line-to-line capacitor and a line-to-ground capacitor from eachindividual electrical conductor. If a metal oxide varistor (MOV)material is used then the filter will be a capacitive filter with overcurrent and surge protection characteristics provided by the MOV-typematerial. The common ground conductive plates and electrode plates willonce again form line-to-line and line-to-ground capacitive platesproviding differential and common mode filtering accept in the case ofhigh transient voltage conditions. During these conditions the MOV-typevaristor material, which is essentially a non-linear resistor used tosuppress high voltage transients, will take effect to limit the voltagewhich may appear between the electrical conductors.

[0020] In a further embodiment a ferrite material may be used addingadditional inherent inductance to the differential and common modefilter arrangement. As before, the common ground conductive andelectrode plates form line-to-line and line-to-ground capacitive plateswith the ferrite material adding inductance to the arrangement. Use ofthe ferrite material also provides transient voltage protection in thatit to will become conductive at a certain voltage threshold allowing theexcess transient voltage to be shunted to the common ground conductiveplates, effectively limiting the voltage across the electricalconductors.

[0021] It is therefore another main object of the present invention toprovide a component carrier for maintaining one or more surface mountcomponents.

[0022] It is another object of the present invention to provide acomponent carrier which is less susceptible to mechanical stressesimparted upon components during various manufacturing processes.

[0023] It is also an object of the present invention to provide acomponent carrier having an enhanced ground surface which improves thefunctional characteristics of surface mount components coupled to thecomponent carrier.

[0024] These and other objects and advantages of the present inventionare accomplished through the use of a surface mount component carriercomprised of a disk of insulating material having at least twoapertures. The disk is substantially covered by a metalized groundsurface and includes at least two conductive pads surrounding theapertures, and insulating bands which surround each conductive pad. Theinsulating bands separate and electrically isolates the conductive padsfrom the metalized ground surface. A specific type of surface mountcomponent, such as a differential and common mode filter, is positionedlengthwise between the two conductive pads and operably coupled to thecarrier. Once the specific type of surface mount component is coupled tothe carrier, the combination can be manipulated, either manually orthrough various types of automated equipment, without subjecting thesurface mount component to mechanical and physical stresses normallyassociated with the handling of miniature components. The carrier alsoprovides the added benefit of improved shielding from electromagneticinterference and over voltage dissipation due to the surface area of themetalized ground surface. The same concept for the above describedcarrier is also incorporated into several alternate embodiments, eitherindependently or embedded within electronic connectors.

[0025] These numerous other arrangements and configurations along withother objects and advantages which implement and build on the presentinvention will become more readily apparent from a reading of thedetailed description, the drawings and the claims taken in conjunctionwith the disclosed versatility and wide spread application of specifictypes of differential and common mode filters within the scope of thepresent invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 shows an exploded perspective view of a differential andcommon mode filter in accordance with the present invention;

[0027]FIG. 1A shows an exploded perspective view of an alternateembodiment of the filter shown in FIG. 1;

[0028]FIG. 2 provides schematic diagrams of the filter shown in FIG. 1with

[0029]FIG. 2A being a pure schematic representation and

[0030]FIG. 2B being a schematic representation of the physicalarchitecture;

[0031]FIG. 3 is an exploded perspective view of a multi-conductordifferential and common mode filter for use in connector applications;

[0032]FIG. 4 shows schematic representations of the differential andcommon mode filter and prior art filters with

[0033]FIG. 4A being a multi-capacitor component as found in the priorart and

[0034]FIG. 4B being the electrical representation of the physicalembodiment of the differential and common mode filter of FIG. 3;

[0035]FIG. 5 is a top plan view of the plurality of common groundconductive and electrode plates which make up a high densitymulti-conductor differential and common filter embodiment;

[0036]FIG. 6 shows a surface mount chip embodiment of a differential andcommon mode filter with

[0037]FIG. 6A being a perspective view and

[0038]FIG. 6B showing an exploded perspective view of the same;

[0039]FIG. 7 shows a multi-filter surface mount component with

[0040]FIG. 7a being a top plan view of the filter;

[0041]FIGS. 7b through 7 d shows top plan views of internal electrodelayers; and

[0042]FIG. 7e shows a front elevational view in cross section of thefilter shown in FIG. 7a;

[0043]FIG. 8 shows a high power embodiment of the differential andcommon mode filter with

[0044]FIG. 8A being a schematic representation of the filter and

[0045]FIG. 8B being a partial schematic/block diagram of the same;

[0046]FIG. 9 shows a further alternate embodiment of the presentinvention;

[0047]FIG. 9a is an exploded prospective view of an alternatemulti-conductor differential and common mode filter for use in connectorapplications;

[0048]FIG. 9b is a front elevational view of the filter shown in FIG.9a;

[0049]FIG. 9c is an electrical representation of the physical embodimentof the filter shown in FIG. 9a; and

[0050]FIG. 9d is an alternate electrical representation of the physicalembodiment of the filter shown in FIG. 9a;

[0051]FIG. 10 is an exploded view of the individual internal layerswhich makeup a multi-component strip filter wherein each internal layershown is a bottom plan view of the layer;

[0052]FIG. 11 shows the multi-component strip filter shown in FIG. 10,where

[0053]FIG. 1A is a top plan view,

[0054]FIG. 11B is front side elevational view,

[0055]FIG. 11C is a back side elevational view and

[0056]FIG. 11D is a bottom plan view;

[0057]FIG. 12 is an elevational view in cross section of a single-sidedsurface mount component carrier of the present invention;

[0058]FIG. 13 is a top plan view of the surface mount component carriershown in FIG. 12;

[0059]FIG. 14 is an elevational view in cross section of a double-sidedsurface mount component carrier of the present invention;

[0060]FIG. 15 is a top plan view of the surface mount component carriershown in FIG. 14;

[0061]FIG. 16 is an exploded perspective view of the connector carrierof the present invention in operable cooperation with a standardconnector shell and a multi-conductor filter;

[0062]FIG. 17 is a partial perspective view of a further embodiment of aconnector surface mount component carrier of the present invention; and

[0063]FIG. 18 is a partial, top plan view of the connector surface mountcomponent carrier shown in FIG. 17.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0064] Specific types of surface mount components such as differentialand common mode filters as are disclosed in application Ser. No.09/008,769, now U.S. Pat. No. 6,097,581, which is a continuation-in-partof application Ser. No. 08/841,940, now U.S. Pat. No. 5,909,350, both ofwhich are incorporated herein by reference.

[0065] Due to the continued and increasing use of electronics in dailylife and the amount of electromagnetic interference (EMI) and emissionsgenerated, new world electromagnetic compatibility (EMC) requirementsare being specified daily for use in such diverse applications as in thehome, hospitals, automotive, aircraft and satellite industries. Thepresent invention is directed towards a physical architecture for anelectronic component which provides EMI suppression, broad band I/O-linefiltering, EMI decoupling noise reduction and surge protection in oneassembly.

[0066] To propagate electromagnetic energy two fields are required, anelectric and magnetic. Electric fields couple energy into circuitsthrough the voltage differential between two or more points. Magneticfields couple energy into circuits through inductive coupling. Magneticfields originate from currents flowing in a path which could simplyconsist of a loop of wire. In such loops both fields exist and are alsoincluded within circuit traces found on printed circuit boards. Thesefields start to diverge at frequencies above 1 MHz.

[0067] As previously noted, propagated electromagnetic energy is thecross product of both electric and magnetic fields. Typically, emphasisis placed on filtering EMI from circuit conductors carrying DC to highfrequency noise. This can be explained for two reasons, the first beingthat a changing electric field in free space gives rise to a magneticfield and second because a time varying magnetic flux will give rise toan electric field. As a result a purely electric or magnetic timevarying field cannot exist. Fields may be primarily electric orprimarily magnetic but neither can be generated exclusively.

[0068] The main cause of radiated emission problems are due to the twotypes of conducted currents, differential and common mode. The fieldsgenerated by these currents result in EMI emissions. Differential mode(DM) currents are those currents which flow in a circular path in wires,circuit board traces and other conductors in a manner in which the fieldrelated to these currents originates from the loop defined by theconductors.

[0069] Common and differential mode currents differ in that they flow indifferent circuit paths. Common mode noise currents are surfacephenomena relative to ground and, for example, travel on the outer skinof cables which are often grounded to the chassis. To reduce, minimizeor suppress the noise it is necessary to provide a low impedance path toground while simultaneously shortening the overall noise current loop.

[0070] Turning now to FIG. 1, an exploded perspective view ofdifferential and common mode filter 10's physical architecture is shown.Filter 10 is comprised of a plurality of common ground conductive plates14 at least two electrode plates 16 a and 16 b where each electrodeplate 16 is sandwiched between two common ground conductive plates 14.At least one pair of electrical conductors 12A and 12B is disposedthrough insulating apertures 18 or coupling apertures 20 of theplurality of common ground conductive plates 14 and electrode plates 16a and 16 b with electrical conductors 12A and 12B also being selectivelyconnected to coupling apertures 20 of electrode plates 16 a and 16 b.Common ground conductive plates 14 consist entirely of a conductivematerial such as metal in the preferred embodiment. At least one pair ofinsulating apertures 18 are disposed through each common groundconductive plate 14 to allow electrical conductors 12 to pass throughwhile maintaining electrical isolation between common ground conductiveplates 14 and electrical conductors 12. The plurality of common groundconductive plates 14 may optionally be equipped with fastening apertures22 arranged in a predetermined and matching position to enable each ofthe plurality of common ground conductive plates 14 to be coupledsecurely to one another through standard fastening means such as screwsand bolts. Fastening apertures 22 may also be used to securedifferential and common mode filter 10 to another surface such as anenclosure or chassis of the electronic device filter 10 is being used inconjunction with.

[0071] Electrode plates 16 a and 16 b are similar to common groundconductive plates 14 in that they are comprised of a conductive materialand have electrical conductors 12A and 12B disposed through apertures.Unlike common ground conductive plates 14, electrode plates 16 a and 16bi are selectively electrically connected to one of the two electricalconductors 12. While electrode plates 16, as shown in FIG. 1, aredepicted as smaller than common ground conductive plates 14 this is notrequired but in this configuration has been done to prevent electrodeplates 16 from interfering with the physical coupling means of fasteningapertures 22.

[0072] Electrical conductors 12 provide a current path which flows inthe direction indicated by the arrows positioned at either end of theelectrical conductors 12 as shown in FIG. 1. Electrical conductor 12Arepresents an electrical signal conveyance path and electrical conductor12B represents the signal return path. While only one pair of electricalconductors 12A and 12B is shown, Applicant contemplates differential andcommon mode filter 10 being configured to provide filtering for aplurality of pairs of electrical conductors creating a high densitymulti-conductor differential and common mode filter.

[0073] The final element which makes up differential and common modefilter 10 is material 28 which has one or a number of electricalproperties and surrounds the center common ground conductive plate 14,both electrode plates 16 a and 16 b and the portions of electricalconductors 12A and 12B passing between the two outer common groundconductive plates 14 in a manner which completely isolates all of theplates and conductors from one another except for the connection createdby the conductors 12A and 12B and coupling aperture 20.

[0074] The electrical characteristics of differential and common modefilter 10 are determined by the selection of material 28. If adielectric material is chosen filter 10 will have primarily capacitivecharacteristics. Material 28 may also be a metal oxide varistor materialwhich will provide capacitive and surge protection characteristics.Other materials such as ferrites and sintered polycrystalline may beused wherein ferrite materials provide an inherent inductance along withsurge protection characteristics in addition to the improved common modenoise cancellation that results from the mutual coupling cancellationeffect. The sintered polycrystalline material provides conductive,dielectric, and magnetic properties. Sintered polycrystalline isdescribed in detail in U.S. Pat. No. 5,500,629 which is hereinincorporated by reference.

[0075] Still referring to FIG. 1, the physical relationship of commonground conductive plates 14, electrode plates 16 a and 16 b, electricalconductors 12A and 12B and material 28 will now be described in moredetail. The starting point is center common ground conductive plate 14.Center plate 14 has the pair of electrical conductors 12 disposedthrough their respective insulating apertures 18 which maintainelectrical isolation between common ground conductive plate 14 and bothelectrical conductors 12A and 12B. On either side, both above and below,of center common ground conductive plate 14 are electrode plates 16 aand 16 b each having the pair of electrical conductors 12A and 12Bdisposed there through. Unlike center common ground conductive plate 14,only one electrical conductor, 12A or 12B, is isolated from eachelectrode plate, 16 a or 16 b, by an insulating aperture 18. One of thepair of electrical conductors, 12A or 12B, is electrically coupled tothe associated electrode plate 16 a or 16 b respectively throughcoupling aperture 20. Coupling aperture 20 interfaces with one of thepair of electrical conductors 12 through a standard connection such as asolder weld, a resistive fit or any other method which will provide asolid and secure electrical connection. For differential and common modefilter 10 to function properly, upper electrode plate 16 a must beelectrically coupled to the opposite electrical conductor 12A than thatto which lower electrode plate 16 b is electrically coupled, that beingelectrical conductor 12B. Differential and common mode filter 10optionally comprises a plurality of outer common ground conductiveplates 14. These outer common ground conductive plates 14 provide asignificantly larger ground plane which helps with attenuation ofradiated electromagnetic emissions and provides a greater surface areain which to dissipate over voltages and surges. This is particularlytrue when plurality of common ground conductive plates 14 are notelectrically coupled to circuit or earth ground but are relied upon toprovide an inherent ground. As mentioned earlier, inserted andmaintained between common ground conductive plates 14 and both electrodeplates 16 a and 16 b is material 28 which can be one or more of aplurality of materials having different electrical characteristics.

[0076] Inherent ground 34 will be described in more detail later but forthe time being it may be more intuitive to assume that it is equivalentto earth or circuit ground. To couple inherent ground 34, which centerand additional common ground conductive plates 14 form, one or more ofcommon ground conductive plates 14 are coupled to circuit or earthground by common means such as a soldering or mounting screws insertedthrough fastening apertures 22 which are then coupled to an enclosure orgrounded chassis of an electrical device. While differential and commonmode filter 10 works equally well with inherent ground 34 coupled toearth or circuit ground, one advantage of filter 10's physicalarchitecture is that a physical grounding connection is unnecessary.

[0077] Referring again to FIG. 1 an additional feature of differentialand common mode filter 10 is demonstrated by clockwise andcounterclockwise flux fields, 24 and 26 respectively. The direction ofthe individual flux fields is determined and may be mapped by applyingAmpere's Law and using the right hand rule. In doing so an individualplaces their thumb parallel to and pointed in the direction of currentflow through electrical conductors 12A or 12B as indicated by the arrowsat either ends of the conductors. Once the thumb is pointed in the samedirection as the current flow, the direction in which the remainingfingers on the person's hand curve indicates the direction of rotationfor the flux fields. Because electrical conductors 12A and 12B arepositioned next to one another and represent a single current loop asfound in many I/O and data line configurations, the currents enteringand leaving differential and common mode filter 10 are opposed therebycreating opposed flux fields which cancel each other and minimizeinductance. Low inductance is advantageous in modem I/O and high speeddata lines as the increased switching speeds and fast pulse rise timesof modem equipment create unacceptable voltage spikes which can only bemanaged by low inductance surge devices.

[0078] It should also be evident that labor intensive aspects of usingdifferential and common mode filter 10 as compared to combining discretecomponents found in the prior art provides an easy and cost effectivemethod of manufacturing. Because connections only need to be made toeither ends of electrical conductors 12 to provide a differential modecoupling capacitor and two common mode decoupling capacitors, time andspace are saved.

[0079]FIG. 1A shows an alternative embodiment of filter 10 whichincludes additional means of coupling electrical conductors or circuitboard connections to filter 10. Essentially, the plurality of commonground conductive plates 14 are electrically connected to an outer edgeconductive band or surface 14 a. Also each electrode plate 16 a and 16 bhas its own outer edge conductive band or surface, 40A and 40Brespectively. To provide electrical connections between electrode plate16 a and 16 b and their respective conductive band 40A and 40B while atthe same time maintaining electrical isolation between other portions offilter 10, each electrode plate 16 is elongated and positioned such thatthe elongated portion of electrode plate 16 a is directed opposite ofthe direction electrode plate 16 b is directed. The elongated portionsof electrode plates 16 also extend beyond the distance in which theplurality of common ground conductive plates 14 extend with theadditional distance isolated from outer edge conductive bands 40A and40B by additional material 28. Electrical connection between each of thebands and their associated plates is accomplished through physicalcontact between each band and its associated common ground conductive orelectrode plate.

[0080]FIG. 2 shows two representations of differential and common modefilter 10. FIG. 2A is a schematic representation demonstrating thatfilter 10 provides a line-to-line capacitor 30 between and coupled toelectrical conductors 12A and 12B and two line-to-ground capacitors 32each coupled between one of the pair of the electrical conductors 12 andinherent ground 34. Also shown in dashed lines is inductance 36 which isprovided if material 28 is comprised of a ferrite material, as describedin more detail later.

[0081]FIG. 2B shows a quasi-schematic of the physical embodiment offilter 10 and how it correlates with the capacitive components shown inFIG. 2A. Line-to-line capacitor 30 is comprised of electrode plates 16 aand 16 b where electrode plate 16 a is coupled to one of the pair ofelectrical conductors 12A with the other electrode plate 16 b beingcoupled to the opposite electrical conductor 12B thereby providing thetwo parallel plates necessary to form a capacitor. Center common groundconductive plate 14 acts as inherent ground 34 and also serves as one ofthe two parallel plates for each line-to-ground capacitor 32.

[0082] The second parallel plate required for each line-to-groundcapacitor 32 is supplied by the corresponding electrode plate 16. Bycarefully referencing FIG. 1 and FIG. 2B, the capacitive platerelationships will become apparent. By isolating center common groundconductive plate 14 from each electrode plate 16 a or 16 b with material28 having electrical properties, the result is a capacitive networkhaving a common mode bypass capacitor 30 extending between electricalconductors 12A and 12B and line-to-ground decoupling capacitors 32coupled from each electrical conductor 12A and 12B to inherent ground34.

[0083] An alternate embodiment of the present invention is differentialand common mode multi-conductor filter 110 shown in FIG. 3. Filter 110is similar to filter 10 of FIGS. 1 and 1A in that it is comprised of aplurality of common ground conductive plates 112 and a plurality ofconductive electrodes 118 a thru 118 h to form differential modecoupling capacitors and common mode decoupling capacitor arrangementswhich act on a plurality of pairs of electrical conductors, not shown inFIG. 3 but similar to electrical conductors 12A and 12B shown in FIGS. 1and 1A. As described earlier for the single pair conductor filter 10shown in FIG. 1, common ground conductive plates 112, conductiveelectrodes 118 and the plurality of electrical conductors are isolatedfrom one another by a pre-selected material 122 having predeterminedelectrical characteristics such as dielectric material, ferritematerial, MOV-type material and sintered polycrystalline material. Eachof the plurality of common ground conductive plates 112 has a pluralityof insulating apertures 114 in which electrical conductors pass whilemaintaining electrical isolation from the respective common groundconductive plates 112. To accommodate a plurality of electricalconductor pairs, differential and common mode filter 110 must employ amodified version of the electrode plates described in FIGS. 1 and 1A.

[0084] To provide multiple independent conductive electrodes for eachpair of electrical conductors, a support material 116 comprised of oneof the materials 122 containing desired electrical properties is used.Support plate 116A is comprised of a plurality of conductive electrodes118 b, 118 c, 118 e and 118 h printed upon one side of plate 116A withone coupling aperture 120 per electrode. Support plate 116B is alsocomprised of a plurality of conductive electrodes 118 a, 118 d, 118 fand 118 g printed upon one side of plate 116B. Support plates 116A and116B are separated and surrounded by a plurality of common groundconductive plates 112. The pairs of incoming electrical conductors eachhave a corresponding electrode pair within filter 110. Although notshown, the electrical conductors pass through the common groundconductive plates 112 and the respective conductive electrodes.Connections are either made or not made through the selection ofcoupling apertures 120 and insulating apertures 114. The common groundconductive plates 112 in cooperation with conductive electrodes 118 athru 118 h perform essentially the same function as electrode plates 16a and 16 b of FIGS. 1 and 1A.

[0085] As described for FIG. 3, to provide multiple independentcomponents for a number of pairs of electrical conductors, material 122also serves as support material 116 which is used to fabricate first andsecond electrode plates 676 and 678. First electrode plate 676 is madeup of first and second conductive electrodes 682 and 686 and blockingelectrode 688, all printed upon one side of support material 116. Secondelectrode plate 678 is made up of first and second conductive electrodes684 and 690 and blocking electrode 692, again printed upon one side ofsupport material 116. First and second electrode plates 676 and 678 arethen separated and surrounded by common ground conductive plates 112.What differs in filter 680 from previous embodiments which allows forthe combination of differential and common mode filters with built inchassis and board noise blocking capacitors is the configuration offirst and second conductive electrodes and blocking electrodes on firstand second electrode plates 676 and 678. First and second conductiveelectrodes 686 and 688 of first electrode plate 676 each include onecoupling aperture 120 disposed in the electrode. Blocking electrode 682is formed to partially surround first and second conductive electrodes686 and 688 and includes a plurality of insulating apertures 114 andcoupling apertures 120. Second electrode plate 678 is identical to firstelectrode plate 676 with first and second conductive electrodes 690 and692 corresponding to first and second conductive electrodes 686 and 688and blocking electrode 684 corresponding with blocking electrode 682.

[0086] Again referring to FIG. 3, multi-conductor filter 110 is shownhaving not only a center common ground conductive plate 112 but outercommon ground conductive plates 112. As described in relation to FIGS. 1and 1A these outer common ground conductive plates 112 provide asignificantly larger ground plane for filter 110 which helps withattenuation of radiated electromagnetic emissions, provides a greatersurface area to dissipate and/or absorb over voltages, surges and noise,and effectively acts as a Faraday shield. This is particularly true whenplurality of common ground conductive plates 112 are not electricallyconnected to circuit or earth ground but are instead relied upon toprovide an inherent ground.

[0087]FIG. 4 shows schematic diagrams of prior art multi-capacitorcomponents and differential and common mode multi-conductor filter 110of the present invention. FIG. 4A is a schematic of prior art capacitorarray 130. Essentially, a plurality of capacitors 132 are formed andcoupled to one another to provide common ground 136 for array 130 withopen terminals 134 provided for connecting electrical conductors to eachcapacitor 132. These prior art capacitor arrays only allowed common modedecoupling of individual electrical conductors when open terminal 134 ofeach capacitor 132 was electrically connected to individual electricalconductors.

[0088]FIG. 4B shows a schematic representation of differential andcommon mode multi-conductor filter 110 having four differential andcommon mode filter pin pair pack arrangements. The horizontal lineextending through each pair of electrodes represents the common groundconductive plates 112 with the lines encircling the pairs being theisolation bars 112A. The isolation bars 112A are electrically coupled tocommon ground conductive plates 112 providing an inherent ground gridseparating each of the electrode plates 118 a through 118 h from oneanother. The corresponding conductive electrodes 118 a thru 118 hpositioned on support material plates 116A and 116B, both above andbelow the center common ground conductive plate 112, and formline-to-ground common mode decoupling capacitors. Each plate, commonground plates 112 and support material plates 116A and 116B, isseparated from the others by dielectric material 122. When filter 110 isconnected to paired electrical conductors via coupling apertures 120such as those found in electrode plates 118 a and 118 c, filter 110forms a line-to-line differential mode filtering capacitor.

[0089] A further variation of the present invention is differential andcommon mode multi-conductor filter 680 shown in FIG. 9. Filter 680 hasbeen optimized for use with computer and telecommunications equipmentand in particular has been configured for use with RJ 45 connectors. Toobtain improved filters performance, filter 680 includes built inchassis and circuit board low frequency noise blocking capacitors inaddition to a plurality of differential and common mode filters. Asshown in FIG. 9A, the physical construction of filter 680 issubstantially similar to filter 110, shown in FIG. 3, and is comprisedof a plurality of common ground conductive plates 112, first and secondelectrode plates 676 and 678 having a plurality of conductive electrodesto form multiple differential and common mode filters including chassisand board blocking capacitors. As described for earlier embodiments,common ground conductive plates 112, conductive electrodes 686, 688, 690and 692, blocking electrodes 682 and 684, and the electrical conductors(not shown) which pass through the various plates are all isolated fromone another by material 122. To realize particular predeterminedelectrical characteristics in filter 680, as in all other embodiments ofthe present invention, material 122 can consist of dielectrics,ferrites, MOV-type material or sintered polycrystalline. Each commonground conductive plate 112 includes a plurality of insulating apertures114 in which electrical conductors pass while maintaining electricalisolation from common ground conductive plate 112. To obtain theadditional chassis and board noise blocking capacitors, filter 680employs a modified version of the electrode plates of FIG. 1.

[0090] As is clearly shown in FIG. 9A, when coupled between the variouscommon ground conductive plates 112, first and second electrode plates676 and 678 are arranged in opposite directions from one another. Thisparticular alignment of first and second electrode plates 676 and 678allows filter 680 to have a traditional RJ 45 pin-out configuration whenused in a connector application. It should be noted that Applicantcontemplates other configurations of conductive and blocking electrodesdepending upon the desired pin-out or wiring arrangement desired and theinverted arrangement of first and second electrode plates 676 and 678 isnot required.

[0091] As in other embodiments, a number of electrical conductors willpass through common ground conductive plates 112 and first and secondelectrode plates 676 and 678. Although the electrical conductors areabsent, FIG. 9B shows that this particular embodiment of filter 680 isadapted to accept eight conductors in accordance with RJ 45 connectorstandards. The interaction of the various conductive electrodes withinfilter 680 will now be described by referring FIGS. 9A through 9D withFIG. 9B included to further correlate the electrical representation withthe physical embodiment of filter 680. FIG. 9D is an alternateelectrical representation of filter 680 which should also be referred toas needed. Signal ground (SG) for filter 680 is provided by thecombination of common ground conductive plates 112 which act as aninherent ground. The physical separation of the various conductiveelectrodes of first and second electrode plates 676 and 678 by theconductive plane of common ground conductive plates 112 provides asubstantial ground plane for filter 680 which inherently acts as aground and assists with attenuation of radiated electromagneticadmissions, provides a greater surface area to dissipate and/or absorbover voltages, surges and noise, and effectively acts as a Faradayshield protecting the filter from external electrical noise andpreventing radiation of the same by filter 680.

[0092] Referring to the various electrical conductors (not shown) by thenumbers 1 through 8 as shown in FIGS. 9B, 9C and 9D, the electricalconductors 3 and 5 are connected through coupling apertures 120 to firstand second conductive electrodes 686 and 688 respectively. Electricalconductors 4 and 6 are connected through coupling apertures 120 toconductive electrodes 690 and 692 respectively. Conductors 1 and 7 areconnected through coupling apertures 120 to blocking electrode 684 andelectrical conductors 2 and 8 are similarly connected through couplingapertures 120 to blocking electrode 682. Referring to FIG. 9D,electrical conductors 3 and 6 are filtered differentially by theinteraction of first and second conductive electrodes 686 and 692 whichact as opposing plates to form a line-to-line capacitor betweenelectrical conductors 3 and 6. The same electrical conductors eachreceive common mode filtering through line-to-ground capacitors formedby the interaction of first and second conductive electrodes 686 and 692with common ground conductive plates 112 which forms line-to-groundcapacitors between each electrical conductor and the inherent groundformed by the plurality of common ground conductive plates 112.

[0093] The same relationship exists for electrical conductors 4 and 5which are connected to first and second conductive electrodes 690 and688 respectively. First and second conductive electrodes 690 and 688form line-to-line capacitors and each interacts with common groundconductive plates 112 to form individual common mode filter capacitorsfor each electrical conductor. In addition to the plurality ofdifferential and common mode filters created by the interaction betweenthe various conductive electrodes and common ground conductive plates,chassis and board noise blocking capacitors are also formed by theinteraction of common ground conductive plates 112 and blockingelectrodes 682 and 684. For instance, chassis ground is connected to theelectrical conductors 1 and 7, both of which are electrically connectedthrough coupling apertures 120 to blocking electrode 682 thereby formingone plate of the noise blocking capacitors. The other plate of the noiseblocking capacitors is formed by common ground conductive plates 112which interact with blocking electrode 682. Although interchangeable,electrical conductors 2 and 8 also provide board noise blockingcapacitors formed by the interaction of common ground conductive plates112 and blocking electrode 682. Both the chassis and board blockingnoise capacitors allow the inherent ground formed by common groundconductive plates 112 to be capacitively decoupled thereby blocking lowfrequency electrical noise from the signal carrying conductors. Thisimproves differential and common mode filter performance by essentiallyelectrically cleansing the inherent ground formed by common groundconductive plates 112.

[0094]FIG. 5 illustrates a further embodiment of the present inventionwhich provides input/output data line pair filtering for a large numberof electrical conductor pairs typical of today's high densityinformation and data buses. Differential and common mode high densityfilter 150 is comprised of a plurality of common ground conductiveplates 112 containing a plurality of insulating apertures 114 andconductive electrode plates 116A and 116B each having electrode patterns118, insulating apertures 114 and coupling apertures 120. The stackingsequence is reflected in FIG. 5 recognizing that dielectric materialwill surround each of the individual plates as described for previousembodiments.

[0095] One trend found throughout modem electronic devices is thecontinuous miniaturization of equipment and the electronic componentswhich make up that equipment. Capacitors, the key component indifferential and common mode filter arrangements, have been no exceptionand their size has continually decreased to the point where they may beformed in silicon and imbedded within integrated circuits only seen withthe use of a microscope. One miniaturized capacitor which has becomequite prevalent is the chip capacitor which is significantly smallerthan standard through hole or leaded capacitors. Chip capacitors employsurface mount technology to physically and electrically connect toelectrical conductors and traces found on circuit boards. Theversatility of the architecture of the differential and common modefilter of the present invention extends to surface mount technology asshown in FIG. 6. Surface mount differential and common mode filter 400is shown in FIG. 6A with its internal construction shown in FIG. 6B.Referring to FIG. 6B, common ground conductive plate 412 is sandwichedbetween first differential plate 410 and second differential plate 414.Common ground conductive plate 412 and first and second differentialplates 410 and 414 are each comprised of material 430 having desiredelectrical properties dependant upon the material chosen. As for allembodiments of the present invention, Applicant contemplates the use ofa variety of materials such as but not limited to dielectric material,MOV-type material, ferrite material, film such as Mylar and newer exoticsubstances such as sintered polycrystalline.

[0096] First differential plate 410 includes conductive electrode 416coupled to the top surface of material 430 in a manner which leavesisolation band 418 surrounding the outer perimeter of first differentialplate 410 along three of its four sides. Isolation band 418 is simply aportion along the edge of material 430 that has not been covered byconductive electrode 416. Second differential plate 414 is essentiallyidentical to first differential plate 410 with the exception being itsphysical orientation with respect to that of first differential plate410. Second differential plate 414 is comprised of material 430 havingconductive electrode 426 coupled to the top surface of material 430 insuch a manner as to leave isolation band 428 surrounding the outerperimeter of second differential plate 414 along three of its foursides. What is important to note about first and second differentialplates 410 and 414's physical orientation with respect to one another isthat the one side of each plate in which isolation bands 418 and 428 donot circumscribe, are arranged 180 degrees apart from one another. Thisorientation allows each electrical conductor to be coupled to eitherindividual plate 410 or 414 but not both.

[0097] Common plate 412 is similar in construction to first and seconddifferential plates 410 and 414 in that it too includes material 430with common conductive electrode 424 coupled to its top surface. As canbe seen from FIG. 6B, common plate 412 has two isolation bands 420 and422 positioned at opposite ends. Common plate 412 is aligned in betweenfirst and second differential plates 410 and 414 so that isolation bands420 and 422 are aligned with the ends of first and second differentialplates 410 and 414 which do not have isolation bands. All three plates,common plate 412 and first and second differential plates 410 and 414 donot have any type of conductive surface beneath each plate and thereforewhen the plates are stacked one on top of the other, conductiveelectrode 426 is isolated from common conductive electrode 424 by thebackside of common plate 412. In a similar fashion common conductiveelectrode 424 is isolated from conductive electrode 416 by the backsideof first differential plate 410 which is comprised of material 430.

[0098] Referring now to FIG. 6A the construction of surface mountdifferential and common mode filter 400 will be further described. Oncecommon plate 412 and first and second differential plates 410 and 414are sandwiched together according to the arrangement shown in FIG. 6B, ameans for coupling electrical conductors to the different electrodesmust be included. Electrical conductors are coupled to surface mountdifferential and common mode filter 400 through first differentialconductive band 404 and second differential conductive band 406 whichare isolated from common conductive band 402 by isolation bands 408positioned in between bands 402, 404 and 406. Common conductive band 402and isolation bands 408 extend 360 degrees around the body of filter 400to provide isolation on all four sides. First and second differentialconductive bands 404 and 406 not only extend 360 degrees around filter400 but also extend to cover ends 432 and 434, respectively.

[0099] By referring back and forth between FIGS. 6A and 6B, the couplingbetween the bands and the plates can be seen. First differentialconductive band 404 including end 434 maintains electrical coupling withconductive electrode 416 which does not have isolation band 418extending to the end of first differential plate 410. Seconddifferential conductive band 406 is electrically isolated from commonplate 412 and first differential plate 410 due to isolation band 422 and428 respectively. In a similar fashion to that just described, seconddifferential conductive band 406 including end 432 is electricallycoupled to conductive electrode 426 of second differential plate 414.Due to isolation bands 420 and 418 of common plate 412 and firstdifferential plate 410, second differential conductive band 406 iselectrically isolated from first differential plate 410 and common plate412.

[0100] Electrical coupling of common conductive band 402 to common plate412 is accomplished by the physical coupling of sides 436 of commonconductive band 402 to common conductive electrode 424 which lacksisolation bands along the sides of common plate 412. To maintainelectrical isolation of common conductive electrode 424 from first andsecond differential conductive bands 404 and 406, isolation bands 420and 422 of common plate 412 prevent any physical coupling of ends 432and 434 of first and second differential conductive bands 404 and 406with common conductive electrode 424.

[0101] As with the other embodiments of the differential and common modefilter of the present invention, conductive electrodes 416 and 426 offirst and second differential plates 410 and 414 act as a line-to-linedifferential mode capacitor when electrical conductors are coupled tofirst and second differential conductive bands 404 and 406.Line-to-ground decoupling capacitors are formed between each conductiveelectrode, 416 and 426 respectively, and common conductive electrode 424which provides the inherent ground.

[0102]FIG. 7 shows an alternative multi-component surface mountdifferential and common mode filter which combines two individualfilters into one electronic component. It should be understood that anynumber of individual filters can be incorporated into a singleelectronic component and that the invention is not limited to twoindividual filters. FIG. 7A shows one interconnect arrangement withFIGS. 7B through 7E disclosing the internal electrode and common groundconductive layers. First and second differential conductive bands 154and 156 are coupled to electrode plates 153 and 155 respectively andbands 154′ and 156′ are similarly coupled to electrode plates 153′ and155′. Multi-component surface mount filter 160 is also comprised ofmaterial 166 having predetermined electrical properties, as describedpreviously, disbursed in between the plurality of electrode and commonground conductive layers. Common ground conductive band 164 iselectrically connected to common ground conductive plate 163. Whatshould be noted is that not only does Applicant contemplate multiplecomponents within a single electronic package but that the shape andarrangement and/or length and width of first and second differentialconductive bands 154 and 156 and common conductive band 164 may bevaried to accompany any type of printed circuit board footprintdesirable. The conductive and common bands are only required to beelectrically coupled to the associated electrode plates and commonground conductive plate 163 while maintaining electrical isolation amongone another. The concept disclosed in FIG. 7 could just as easily beextended to incorporate 10, 20 or 100 differential and common modefilters if desired. Multi-component surface mount differential andcommon mode filter 160 is particularly useful for providing filtering tolarge data buses typically consisting of 32 or 64 data lines. These databuses handle digital information at extremely high frequencies emittinglarge amounts of electromagnetic energy and are also extremelysusceptible to over currents and voltage surges which can damagecircuitry and distort data.

[0103]FIGS. 10 and 11 show a further alternative multi-component surfacemount differential and common mode filter designed to provide a strip offilters for varied use. This specific design is for use with multiconductor electronic connectors. As in other embodiments of the presentinvention, strip filter 642 is comprised of a plurality of common groundconductive plates 656 with first and second electrode plates 662 and 664sandwiched in between the various common ground conductive plates 656.Strip filter 642, shown in FIG. 10, has four sets of differential andcommon mode filters. Each common ground conductive plate 656 is etchedupon support material 616 having predetermined electrical properties, asdisclosed throughout the specification, so that portions of material 616act as insulation on either side of each common ground conductive plate656 with only ground extensions 660 extending to the edges of supportmaterial 616. The various first and second electrode plates 662 and 664are also formed on strips of support material 616 so that each electrodeplate is surrounded by material 616 except for electrode extensions 666which extend to the edges of support material 616. As can be seen inFIG. 10, each electrode extension 666 of each first electrode plate 662extends in an opposite direction from the electrode extension 666 of thecorresponding second electrode plate 664. The arrangement of groundextensions 660 and electrode extensions 666 can be reconfigured innumerous patterns as long as a convenient layout for electricalconductor coupling is created As in the various other embodiments of thepresent invention, each differential and common mode filter included instrip filter 642 consists of a first and second electrode plate 662 and664 sandwiched between common ground conductive plates 656 withadditional material having predetermined electrical properties (notshown) disposed between and electrically isolating the various groundand electrode plates from one another. FIG. 11 shows top, bottom andside views of strip filter 642 having first and second differentialconductive bands 652 and 654 running perpendicular to the lengths ofsupport material 616 and slightly overlapping onto the top of stripfilter 642, as shown in FIG. 11A. The bottom of strip filter 642, asshown in FIG. 11D, is the same as the top to allow for surface mountingof strip filter 642. Common ground conductive bands 650 extendvertically up the ends and onto the top and bottom of strip filter 642,as indicated by the portions labeled 650 in FIGS. 11A and 11D.Additional common ground conductive bands 650 are also found on the topand bottom of strip filter 642 but in this configuration they do notextend down the sides. First and second differential conductive bands652 and 654 extend down the corresponding sides of strip filter 642allowing the various electrode extensions 666 of each of the first andsecond electrode plates 662 and 664 to electrically couple to theirrespective conductive bands thereby allowing connection of externalelectrical conductors to the various internal electrode plates of stripfilter 642. For purposes of clarity, the corresponding first and secondelectrode plates 662 and 664 and first and second differentialconductive bands 652 and 654 include suffix designations (a) through (d)which represents each of the four differential and common mode filtersincluded within strip filter 642.

[0104]FIG. 8 shows a high-power embodiment of the differential andcommon mode filter of the present invention. FIG. 8A shows aquasi-schematic representation of the physical arrangement of plateswhich make up the filter shown in FIG. 8B. Referring to both FIGS. 8Aand 8B it can be seen that common ground conductive plate 292 is againsandwiched between two conductive electrode plates, 270 and 270′, whichare individually connected/coupled to electrical conductors 275A and275B. Each conductive electrode plate, 270 and 270′, consists of amaterial 264 having specific predetermined properties, with each platethen having a conductive surface to which electrical connections aremade. After electrical conductors 275A and 275B are connected toconductive electrode plates 270 and 270′, the conductive surface iscoated with insulation. Conductive electrode plates 270 and 270′ arephysically coupled to common ground conductive plate 292 via typicaladhesive material known in the art.

[0105] Illustrated in FIG. 12 is surface mount component carrier 2010for maintaining a ceramic planar surface mount electrical component,such as a differential and common mode filter as is disclosed above andin application Ser. No. 09/008,769, now U.S. Pat. No. 6,097,581, whichis a continuation-in-part of application Ser. No. 08/841,940, now U.S.Pat. No. 5,909,350, both of which are previously incorporated herein byreference.

[0106] Carrier 2010 is a disk comprised of an insulator 2014, such asceramic, having at least two apertures 2018. Insulator 2014 is coveredby a conductive metalized ground surface 2016, at least two conductivepads 2024 surrounding apertures 2018, and insulating bands 2022surrounding each conductive pad 2024. Insulating bands 2022 separate andelectrically isolate conductive pads 2024 from metalized ground surface2016. In the top plan view of carrier 2010, shown in FIG. 13, thepreferred embodiment of the invention is circular in shape with squareinsulating bands 2022 surrounding partially rounded conductive pads2024. Carrier 2010 and its various elements can be formed into manydifferent shapes and Applicant does not intend to limit the scope of theinvention to the particular shapes shown in the drawings.

[0107] Referring again to FIG. 12, in the preferred embodiment,metalized ground surface 2016 covers a substantial portion of the topand sides of carrier 2010. Through-hole plating 2020 covers the innerwalls of aperture 2018 and electrically couples to the correspondingconductive pad 2024. Through-hole plating 2020 provides greater surfacearea for electrical coupling of conductors 2034 to conductive pads 2024as the conductors 2034 are disposed through apertures 2018. Theconfiguration of metalized ground surface 2016, insulating bands 2022and conductive pads 2024 provide the necessary contacts for connecting asurface mount component, such as differential and common mode filter2012, to the upper surface of carrier 2010, which in turn provideselectrical connection between conductors 2034 and surface mountcomponent 2012. The surface mount components referred to, such asdifferential and common mode filter 2012, are provided in standardsurface mount packages which include a number of solder terminations forelectrically coupling the device to external circuitry or in this caseto carrier 2010. Filter 2012 includes first differential electrode band2028 and second differential electrode band 2030 extending from eitherend of filter 2012. Extending from the center of filter 2012 is at leastone and more typically two, common ground conductive bands 2026. Aninsulated outer casing 2032 electrically isolates first and seconddifferential electrode bands 2028 and 2030 and common ground conductivebands 2026 from one another. A top plan view of a standard surface mountdevice as just described is shown in FIG. 18 as differential and commonmode filter 1040. The filter 1040 is comprised of first differentialconductive band 1160, second differential conductive band 1180 and twocommon ground conductive bands 1200. The insulated outer casing 1220separates and electrically isolates each of the various conductive bandsfrom one another.

[0108]FIG. 12 shows filter 2012 positioned upon the top surface ofcarrier 2010 so that the common ground conductive bands 2026 come incontact with the portion of the metalized ground surface 2016 whichseparates both of the insulating bands 2022 from one another. This isaccomplished by positioning differential and common mode filter 2012lengthwise between the two conductive pads 2024 such that firstdifferential electrode band 2028 is in contact with one of the twoconductive pads 2024 and second differential electrode band 2030 comesin contact with the other conductive pad 2024. Once filter 2012 has beenpositioned, by default, insulated outer casing 2032 of filter 2012aligns with portions of insulating bands 2022 thereby maintainingelectrical isolation between the various conductive and electrode bandsof filter 2012. First and second differential conductive bands 2028 and2030 and the common ground conductive bands 2026 consist of solderterminations found in typical surface mount devices. Once filter 2012 ispositioned upon carrier 2010 standard solder re-flow methods areemployed causing the solder terminations to re-flow thereby electricallycoupling and physically bonding filter 2012 to carrier 2010. Customarysolder re-flow methods which can be used include infrared radiation(IR), vapor phase and hot air ovens or any other means which can be usedto expose the solder to sufficiently elevated temperatures. Oncedifferential and common mode surface mount filter 2012 is coupled tocarrier 2010, the combination of the two parts can be manipulated,either manually or through various types of automated equipment, withoutsubjecting filter 2012 to mechanical and physical stresses normallyassociated with the handling of miniature and delicate electroniccomponents.

[0109] Once coupled to carrier 2010, filter 2012 is electricallyconnected to external circuitry through conductors 2034 which mayconsist of wire leads or lengths of flexible wire. Once disposed throughapertures 2018, conductors 2034 are soldered to conductive pads 2024 andwithin apertures 2018. Thru-hole plating 2020 allows solder applied toconductive pads 2024 and conductors 2034 to flow into apertures 2018thereby adhering to the thru-hole plating. Component carrier 2010reduces mechanical and physical stresses such as shock, vibration andvarious thermal conditions which filter 2012 would otherwise besubjected to and provides a complete ground shield for filter 2012.Because carrier 2010 has a greater surface area then filter 2012 and asubstantial portion of that surface area is covered by metalized groundsurface 2016, carrier 2010 acts as a ground shield which absorbs anddissipates electromagnetic interference and over voltages. These addedbenefits improve the overall functional performance and characteristicsof filter 2012.

[0110]FIGS. 14 and 15 illustrate a further alternate embodiment of thepresent invention, that being double-sided carrier 2040. Carrier 2040 isidentical to carrier 2010, as shown in FIG. 12, except that carrier 2040is double-sided and as a bottom surface which is substantially identicalto the top surface. This configuration allows two differential andcommon mode surface mount filters 2012A and 2012B to be mounted to theupper and lower surfaces of carrier 2040. As illustrated in FIG. 14,metalized ground surface 2016 covers substantial portions of the top,sides and bottom of carrier 2040 providing a greater overall surfacearea. The increased surface area of metalized ground surface 2016imparts greater shielding characteristics in carrier 2040 which absorband dissipate electromagnetic interference. In addition, both the topand bottom of carrier 2040 include corresponding conductive pads 2024which are electrically connected to one another by thru-hole plating2020 which covers the inner walls of apertures 2018.

[0111] Double-sided carrier 2040 is also advantageous in that it allowsfor flexibility needed to meet electromagnetic interference (EMI) andsurge protection requirements simultaneously through integration ofdifferent surface mount components on the same carrier substrate. As anexample, a differential and common mode filter, as previously described,could be coupled to the top of carrier 2040 while a MOV device could becoupled on the bottom of carrier 2040 effectively placing the filter andMOV devices in parallel to provide EMI and surge protection in onecompact, durable package. Because carrier 2040 provides a rigid base formaintaining various electronic surface mount components, the componentsthemselves are subjected to less physical stress during manufacturingprocesses which in turn increases yields and lowers manufacturing costs.

[0112]FIG. 15 shows a modified configuration of metalized ground surface2016, conductive pads 2024 and insulating bands 2022. In thisalternative embodiment, insulating bands 2022 have been substantiallyincreased such that the surface area of carrier 2040 is substantiallycovered by insulation as opposed to a metalized ground surface. Thisconfiguration can be used when decreased shield characteristics aredesired or the particular interaction between carrier 2040 and thesurface mount component needs to be precisely controlled. One example iswhen parasitic capacitance values must be maintained below a certainlevel. Note that the particular shapes of insulating bands 2022, shownin FIG. 15, are not necessary. All that is required is that the surfacearea covered by metalized ground surface 2016 be varied which in turnvaries the electrical characteristics of double-sided carrier 2040. Itshould also be noted that the surface pattern shown in FIG. 13 can beused with the double-sided carrier 2040, shown in FIG. 14, or thesurface pattern shown in FIG. 15 could just as easily be used withcarrier 2010, shown in FIG. 12. To obtain further control of theelectrical characteristics of double-sided carrier 2040, one surfacecould be configured as shown in FIG. 15 while the other surface, eithertop or bottom, could be configured as shown in FIG. 13. Altering theupper and lower surface patterns of double-sided carrier 2040 dependingupon the types of surface mount components coupled to carrier 2040allows for obtaining optimal electrical characteristics as needed.

[0113]FIG. 16 shows an exploded prospective view of D-sub connectorshell 2074, connecter carrier 2070 and multi-conductor filter 2080.While carrier 2070 can be used with a variety of filters, Applicantcontemplates multi-conductor filter 2080 being a differential and commonmode multi-conductor filter as disclosed in application Ser. No.09/008,769, now U.S. Pat. No. 6,097,581, which is a continuation-in-partof application Ser. No. 08/841,940, now U.S. Pat. No. 5,909,350, both ofwhich are previously incorporated herein by reference.

[0114] Filter 2080 includes a plurality of apertures 2084 which receivecontact pins (not shown) associated with male D-sub connectors commonlyknown in the art. One example of such a connector is a male D-sub RS-232communications connector found in personal computers for couplingexternal devices such as modems to the computers. To be used in thisembodiment of carrier 2070, filter 2080 must also be formed in the shapeof a parallelogram or D-shape and have dimensions similar to those ofcarrier 2070. Filter 2080 includes plated surface 2082 along itsperiphery which is electrically connected to the common groundconductive plates of filter 2080. In use, conductor carrier 2070receives multi-conductor filter 2080 which abuts against inner shelf2076. Shelf 2076 is coated with a solder re-flow so that once filter2080 is inserted into carrier 2070 and resting upon shelf 2076, standardre-flow methods can be used to solder filter 2080 within carrier 2070.Such standard re-flow methods include the use of infrared radiation(IR), vapor phase and hot air ovens. The subassembly of filter 2080 andcarrier 2070 is then inserted within D-sub connector shell 2074 so thesubassembly is contained within wall 2088 and abutted against shelf 2086which serves as a stop for carrier 2070. Connector carrier 2070 isfabricated from a conductive material such as metal and, to obtain thefull benefits of the present invention, D-sub connector shell 2074 willalso be fabricated from a conductive metallic material. The plurality ofprotuberances 2072 provide a resistive fit for carrier 2070 against wall2088 of D-sub connector shell 2074 which maintains carrier 2070 withinshell 2074 and provides for electrical conduction between plated surface2082 of filter 2080 and shell 2074. As in previous embodiments,electrically coupling the ground connection for multi-conductor filter2080 to carrier 2070 and D-sub connector shell 2074 increases thesurface area provided for absorbing and dissipating electromagneticinterference and over voltages.

[0115] An additional embodiment of the present invention, connectorcarrier 1000, is illustrated in FIG. 17. In this embodiment the surfacemount component carrier is directly incorporated within an electronicconnector. Connector carrier 1000 is comprised of a metalized plasticbase 1120 having a plurality of apertures 980 disposed through base1120, each of which receives a connector pin 1020. Although not shown,portions of each connector pin 1020 extends through base 1120 and out ofthe front 1100 of connector carrier 1000. The portions of pins 1020extending from the front 1100 of carrier 1000 form a male connectorwhich is then, in turn, received by a female connector as is known inthe art. Coupled to both edges of connector carrier 1000, although onlyone edge is shown, is mounting base 1140 which elevates base 1120 from asurface such as a printed circuit board. The particular embodiment ofconnector 1000 shown in FIG. 17 is of a right angle connector in whichthe tips of pins 1020 would be inserted within apertures in a printedcircuit board. Pins 1020 would then be soldered to the individualapertures or pads in the printed circuit board to provide electricalconnection between pins 1020 and any circuitry on the printed circuitboard. To provide for the coupling of a plurality of differential andcommon mode filters 1040 between the various connector pins 1020, twoinsulating bands 1060 and 1070 are provided to electrically isolate eachof the connector pins 1020 from the metalized plastic base 1120 whichcovers substantially all of the surface area of connector carrier 1000.

[0116] Referring to FIG. 18, the relationship between insulating bands1060 and 1070, metalized plastic base 1120 and differential and commonmode filter 1040 will be explained in more detail. While only oneexample is shown, both insulating bands 1060 and 1070 include aplurality of conductive pads 1080 which surround apertures 980.Conductive pads 1080 are electrically coupled to connector pins 1020disposed through apertures 980. Insulating bands 1060 and 1070 provide anon-conductive barrier between the conductive pads 1080 and themetalized plastic base 1120. Surface mount components, such asdifferential and common mode filter 1040, are positioned betweeninsulated bands 1060 and 1070 so that first differential conductive band1160 of filter 1040 comes in contact with a portion of a conductive pad1080 and second differential conductive band 1180 comes in contact witha portion of an opposite conductive pad 1080. Insulated outer casing1220 of filter 1040 slightly overlaps onto each insulating band 1060 and1070 and metalized plastic base 1120 to maintain electrical isolation offirst and second differential conductive bands 1160 and 1180 andmetalized plastic base 1120 of connector carrier 1000. Because metalizedplastic base 1120 runs between insulating bands 1060 and 1070, commonground conductive bands 1200 of filter 1040 come in contact with themetalized plastic base 1120. As described earlier, each of the variousconductive bands of filter 1040 are comprised of solder terminationswhich, when subjected to known solder re-flow methods, physically andelectrically couple to any metallic surfaces which they come in contactthereby permanently coupling the surface mount components, i.e. filter1040, to connector carrier 1000. As in the previous embodiments,connector carrier 1000 allows miniature, fragile surface mountcomponents to be used without subjecting those components to increasedphysical stress which can cause damage to the components, loweringproduction yields and increasing overall production costs. Metalizedplastic base 1120 also provides a large conductive surface areaconnected to the ground terminations of filter 1040 improving the groundshield used to absorb and dissipate electromagnetic interference andover voltages.

[0117] As can be seen, many different applications of the differentialand common mode filter architecture with a carrier are possible andreview of several features universal to all the embodiments must benoted. First, the material having predetermined electrical propertiesmay be one of a number in any of the embodiments including but notlimited to dielectric material, metal oxide varistor material, ferritematerial and other more exotic substances such as Mylar film or sinteredpolycrystalline. No matter which material is used, the combination ofcommon ground conductive plates and electrode conductive plates createsa plurality of capacitors to form a line-to-line differential couplingcapacitor between and two line-to-ground decoupling capacitors from apair of electrical conductors. The material having electrical propertieswill vary the capacitance values and/or add additional features such asover-voltage and surge protection or increased inductance, resistance,or a combination of all the above.

[0118] In fact the differential and common mode filter, although notshown, could easily be fabricated in silicon and directly incorporatedinto integrated circuits for use in such applications as communicationchips. The differential and common mode filter would be embedded andfilter communication or data lines directly from their circuit boardterminal connections, thus reducing circuit board real estaterequirements and further reducing overall circuit size while havingsimpler production requirements. Integrated circuits are already beingmade having capacitors etched within the silicone foundation whichallows the architecture of the present invention to readily beincorporated with technology available today.

[0119] Second, in all embodiments whether shown or not, the number ofplates, both common conductive and electrode, can be multiplied tocreate a number of capacitive elements in parallel which thereby add tocreate increased capacitance values.

[0120] Third, additional common ground conductive plates surrounding thecombination of a center conductive plate and a plurality of conductiveelectrodes may be employed to provide an increased inherent ground andsurge dissipation area and a true Faraday shield in all embodiments.Additional common ground conductive plates can be employed with any ofthe embodiments shown and is fully contemplated by Applicant.

[0121] Finally, from a review of the numerous embodiments it should beapparent that the shape, thickness or size may be varied depending onthe electrical characteristics desired or upon the application in whichthe filter is to be used due to the physical architecture derived fromthe arrangement of common ground conductive and conductive electrodeplates.

[0122] Although the principles, preferred embodiments and preferredoperation of the present invention have been described in detail herein,this is not to be construed as being limited to the particularillustrative forms disclosed. They will thus become apparent to thoseskilled in the art that various modifications of the preferredembodiments herein can be made without departing from the spirit orscope of the invention as defined by the appended claims.

I claim:
 1. A differential mode and common mode filter arrangementcomprising: paired electrodes of substantially the same size and shape;the paired electrodes are oppositely positioned relative to each other;a material having at least predetermined properties; an internalconductive shielding means for attenuation of both internal and externalradiated electromagnetic energy and that at least dissipates overvoltages; an external conductive means for improving the performance ofthe internal conductive shielding means for attenuation; the pairedelectrodes are spaced apart by the material; the paired electrodes areconductively isolated from each other; and wherein the paired electrodesare conductively isolated from both the internal conductive shieldingmeans for attenuation and the external conductive means for improvingthe performance of the internal conductive shielding means forattenuation.
 2. The differential mode and common mode filter arrangementof claim 1, wherein the material having predetermined properties is amaterial having dielectric properties.
 3. The differential mode andcommon mode filter arrangement of claim 1, wherein the material havingpredetermined properties is a material having ferrite properties.
 4. Thedifferential mode and common mode filter arrangement of claim 1, whereinthe material having predetermined properties is a material havingvaristor properties.
 5. The differential mode and common mode filterarrangement of claim 1 operable as a differential mode and common modebypass filter arrangement.
 6. The differential mode and common modefilter arrangement of claim 1 operable as a portion of a capacitivenetwork.
 7. A circuit comprising: at least the differential mode andcommon mode filter arrangement of claim
 1. 8. A differential mode andcommon mode filter arrangement comprising: an electrode arrangementhaving; a plurality of electrodes, and wherein the electrodes of theplurality of electrodes are arranged spaced-apart by a material havingat least ferromagnetic properties; a first electrode of the plurality ofelectrodes positioned below a second electrode of the plurality ofelectrodes; a third electrode of the plurality of electrodes positionedabove the second electrode; a fourth electrode of the plurality ofelectrodes positioned above the third electrode; a fifth electrode ofthe plurality of electrodes positioned above the fourth electrode; thesecond electrode and the fourth electrode are conductively isolated fromeach other; the first electrode, the third electrode and the fifthelectrode are conductively coupled to one another; the first electrode,the third electrode and the fifth electrode are conductively isolatedfrom the second electrode and the fourth electrode; and at least a firstenergy pathway and a second energy pathway that are conductivelyisolated from each other; a common energy pathway located amid the firstenergy pathway and the second energy pathway; the second electrode isconductively coupled to the first energy pathway; the fourth electrodeis conductively coupled to the second energy pathway; the firstelectrode, the third electrode and the fifth electrode are conductivelycoupled to the common energy pathway; and wherein the common energypathway is conductively isolated from the first energy pathway and thesecond energy pathway.
 9. The differential mode and common mode filterarrangement of claim 8, wherein the third electrode is the centralelectrode of the plurality of electrodes.
 10. The differential mode andcommon mode filter arrangement of claim 9, wherein the first electrode,the third electrode and the fifth electrode are substantially the samesize; and wherein the second electrode and the fourth electrode aresubstantially the same size.
 11. The differential mode and common modefilter arrangement of claim 10, wherein the first electrode, the thirdelectrode and the fifth electrode are substantially the same shape; thesecond electrode and the fourth electrode are substantially the sameshape; and wherein the second electrode and the fourth electrode areshielded from each other.
 12. The differential mode and common modefilter arrangement of claim 10 operable as a differential mode andcommon mode bypass filter arrangement.
 13. The differential mode andcommon mode filter arrangement of claim 11, wherein the first electrode,the third electrode and the fifth electrode are operable as shieldingelectrodes of at least the second electrode and the fourth electrode.14. The differential mode and common mode filter arrangement of claim12, wherein the first electrode, the third electrode and the fifthelectrode are operable as shielding electrodes of at least the secondelectrode and the fourth electrode.
 15. The differential mode and commonmode filter arrangement of claim 13 operable as a portion of acapacitive network.
 16. A circuit comprising: at least the differentialmode and common mode filter arrangement of claim
 15. 17. Thedifferential mode and common mode filter arrangement of claim 11,wherein the first energy pathway and the second energy pathway arepaired conductors; the common energy pathway is a conductive area; andwherein the conductive area is always conductively and electricallyisolated from the paired conductors.
 18. The differential mode andcommon mode filter arrangement of claim 8, wherein the differential modeand common mode filter arrangement is operable for simultaneous commonmode and differential mode filtering with a surge protection function.19. The differential mode and common mode filter arrangement of claim13, wherein the material having ferromagnetic properties is a materialhaving predominately varistor material properties.
 20. The differentialmode and common mode filter arrangement of claim 13, wherein thematerial having ferromagnetic properties is a material havingpredominately dielectric material properties.